The steelyardclepsydra, a special type of clepsydra, had been a chief time-keeping instrument during the Sui-Tang period a nd the earlier stage of Northern Song dynasty.
秤漏是一种特殊类型的漏刻，在隋唐及北宋前期曾是司天机构的主要计时仪器。
2
The steelyardclepsydra, a special type of clepsydra, had been the chief timekeeping instrument during the Sui-Tang period and the earlier stage of the Northern Song dynasty.
秤漏是一种特殊类型的漏刻，在隋唐及北宋前期曾是司天机构的主要计时仪器。
3
According to the record of ancient documents, this paper gives the possible structure of li Lan's steelyardclepsydra, and demonstrates the principle for the stabilization of average flow velocity.